School of Optometry, Indiana University, Bloomington, Indiana, USA.
Ophthalmic Physiol Opt. 2022 May;42(3):571-585. doi: 10.1111/opo.12959. Epub 2022 Feb 16.
To develop an optical model of a child's eye to reveal the impact of target distance and accommodative behaviour on retinal image quality when fitted with multi-zone lenses.
Pupil size, aberration levels and accommodative lag were adjusted for models viewing stimuli at 400, 100, 33 and 20 cm. Distributions of defocus across the pupil and simulated retinal images were obtained. An equivalent 16-point letter was imaged at near viewing distances, while a 0.00 logMAR (6/6) letter was imaged at 400 cm. Multi-zone lenses included those clinically utilised for myopia control (e.g., dual-focus, multi-segmented and aspherical optics).
Viewing distance adjustments to model spherical aberration (SA) and pupil radius resulted in a model eye with wider defocus distributions at closer viewing distances, especially at 20 cm. The increasing negative SA at near reduced the effective add power of dual-focus lenses, reducing the amount of myopic defocus introduced by the centre-distance, 2-zone design. The negative SA at near largely compensated for the high positive SA introduced by the aspheric lens, removing most myopic defocus when viewing at near. A 0.50 D accommodative lag had little impact on the legibility of typical text (16-point) at the closer viewing distances.
All four multi-zone lenses successfully generated myopic defocus at greater viewing distances, but two failed to introduce significant amounts of myopic defocus at the nearest viewing distance due to the combined effects of pupil miosis and negative SA. Typical 16-point type is easily legible at near even in presence of the multi-zone optics of lenses utilised for myopia control and accommodative lag.
开发儿童眼睛的光学模型，揭示目标距离和调节行为对多焦点镜片矫正时视网膜成像质量的影响。
调整瞳孔大小、像差水平和调节滞后，使模型观察距离为 400cm、100cm、33cm 和 20cm 的刺激物。获得瞳孔上的离焦分布和模拟视网膜图像。在近距观察时，对等效的 16 点字母成像，而在 400cm 处对 0.00 对数视力（6/6）字母成像。多焦点镜片包括临床上用于近视控制的镜片（如双焦点、多分段和非球面光学）。
对模型球差（SA）和瞳孔半径的观察距离调整导致模型眼在更近的观察距离下具有更宽的离焦分布，尤其是在 20cm 时。近距处负 SA 的增加降低了双焦点镜片的有效附加屈光度，减少了中心距离、2 区设计引入的近视离焦量。近距处的负 SA 很大程度上补偿了非球面透镜引入的高正 SA，在近距观察时消除了大部分近视离焦。0.50 D 的调节滞后对更近观察距离的典型文字（16 点）的清晰度影响不大。
所有四种多焦点镜片在更远的观察距离都成功地产生了近视离焦，但由于瞳孔缩小和负 SA 的综合影响，两种镜片在最近的观察距离都未能引入大量的近视离焦。即使存在用于近视控制和调节滞后的多焦点光学镜片，典型的 16 点类型在近距时也很容易辨认。
